| commit | 9e2d016bd4cf543f5473df8d3e5ca9aa4538e631 | |
| author | Kelsey Gilbert <kelsey.gilbert@mozilla.com> | |
| Mon, 23 Jan 2023 22:13:17 +0000 (23 22:13 +0000) | ||
| committer | Kelsey Gilbert <kelsey.gilbert@mozilla.com> | |
| Mon, 23 Jan 2023 22:13:17 +0000 (23 22:13 +0000) | ||
| tree | cd84524d86c37c349cc915f66c9f4cc55295b5b9 | treesnapshot (tar.gz zip) |
| parent | 70f8fd53cce1964061b85c637eafe1fee7eb8da0 | commitdiff |
Bug 1799258 - Do color-management on Windows+DComp via IDCompositionFilterEffects. r=sotaro
+ Add gfx.color_management.rec709_gamma_as_srgb:true. :'(
In particular, rec709(16/255) -> srgb(31/255). Even though it's
technically correct, it's practically-speaking incorrect, since that's
not what Chrome does, nor what the web expected for years and years.
In practice, basically everyone expects gamma to just be completely
ignored.
What people expect:
* Pretend gamut is srgb(==rec709), but stretch this naively for the
display. If you have a display-p3-gamut display, srgb:0.5 expects to
be displayed as display:0.5, which will be display-p3:0.5 to the eyes.
* Pretend all content gammas (TFs) are srgb(!=rec790), and then bitcast this
naively for the display. E.g. rec709(16/255) should
display the same as srgb(16/255), not srgb(31/255). (Note: display-p3
uses srgb gamma) But if your display has e.g. gamma=3.0, don't
convert or compensate.
This is a formalization of what you get when you spend decades ignoring
color management, and people build things based on behavior-in-practice,
not behavior-in-theory.
Also:
+ gfx.color_management.native_srgb:true for Windows, so we don't use the
display color profile, which no one else does.
+ Add rec2020_gamma_as_rec709, so we have a path towards maybe having
rec2020 use its correct transfer function, rather than srgb (like
rec709).
Differential Revision: https://phabricator.services.mozilla.com/D161857
+ Add gfx.color_management.rec709_gamma_as_srgb:true. :'(
In particular, rec709(16/255) -> srgb(31/255). Even though it's
technically correct, it's practically-speaking incorrect, since that's
not what Chrome does, nor what the web expected for years and years.
In practice, basically everyone expects gamma to just be completely
ignored.
What people expect:
* Pretend gamut is srgb(==rec709), but stretch this naively for the
display. If you have a display-p3-gamut display, srgb:0.5 expects to
be displayed as display:0.5, which will be display-p3:0.5 to the eyes.
* Pretend all content gammas (TFs) are srgb(!=rec790), and then bitcast this
naively for the display. E.g. rec709(16/255) should
display the same as srgb(16/255), not srgb(31/255). (Note: display-p3
uses srgb gamma) But if your display has e.g. gamma=3.0, don't
convert or compensate.
This is a formalization of what you get when you spend decades ignoring
color management, and people build things based on behavior-in-practice,
not behavior-in-theory.
Also:
+ gfx.color_management.native_srgb:true for Windows, so we don't use the
display color profile, which no one else does.
+ Add rec2020_gamma_as_rec709, so we have a path towards maybe having
rec2020 use its correct transfer function, rather than srgb (like
rec709).
Differential Revision: https://phabricator.services.mozilla.com/D161857